Wood pavement.



H. G. JENNISON.

Patented May 6, 1919.

FIELE HARRY G. JENNISQN, 0F TULEDQ, OHIO.

woon ravnivinn'r.

Tl ,Sllfddilill.

Specification of Letters Patent.

Patented lday *8, laid.

Application filed catcher 2.3, 191%. Serial lilo. $68,177.

This invention utility in the prcparation bf'timber and the grouping of elements or blocks of material, having especial. value when the above features are combined in the production of deformation minimized Wood blocks for incorporation into pavements or Referring to the drawing:

Figure l is a plan view of a paving block shrunk;

Fig. 2 is a plan view of an unshrunlr pav- Zing block embodying features of the invention;

Fig. 3 is a fragmentary plan view of; a pavement embodying features of the mvention after shrinking has occurred;

Fig. 5 is a perspective view of a paving block of Fig. 2; and

Fig. 5 is a perspective view of a paving block with expansion takeaip as well as shrinkage provision.

The seasoned or dry block 1, impregnated say with. a hydrocarbon, and installed in a floor protected. tron'i moisture will in its aging shrink as n'mch as 7%, enlarging to an objectionable extent the intermediate lill ing' space between the blocks and exposing);

the corners to extra wear and fracture, thereby reducing the life or": the pavement as a smiaith floor.

The paving; block of Figs. E2, i, has the Wear face 2 parallel to the face 3, each across the grain of the timber of thebloclr and connected by the bloclr side walls 4- into which extend the openings 0 inwardly from the wall and the full. length of the side 4, as well part way across the tacos 3, 2, to intercept the larger or longer are age rings (3. These blocks having' the wear faces 2 upon such dry use are subject to shrinlntge action, but the pulling togretl'ier or diameter reducing; action. of the longer are age rings (Sis distributed and dissipated by each opening 5, and the shrunk block has its wear face 7 With the openings 8 each taking a portion of the shrinkage. With two openings intercepting the longer are age rings, the overall shrinkage in length of the block of Fig. 3 is approximately one third the shrinkage of the unopened block 01'? Fig. 1.

Instead of merely interrupting the continuity of the longer are rings, in the block of 5, this block 9 has the openings 10' initially configured to permit expansion of these larger are age rings. These blocks are designed to stand weathering and Within themselves dissipate nearly all the dimensional changes due thereto, thereby producmg most simply a dependable wood block pavement. i

The growth rings appear to act as units under moisture variations. The shorter rings which run out the side Walls of the block, having but a fractional extent of'the block involved in their change, do not prove such disturbing; factors as those rings approximating the longer transverse block dimensions. Creating; openings by rupturing these major or longer are age rings in the blocks does not interfere with the deformation of the rings. but the added number of places from which to pull, or into which to push, dissipates these changes to such an extent within the block that the ex cess becomes such a negligible quantity as not to disturb regular laying. These conditions arise with impregnated, creosoted and natural wood blocks," and the ring opening treatment effectively minimizes external di-' mension deformation by dissipating inside thereof. I

What is claimed and it is desired to secure by Letters Patcntis:

1. it pavement comprisingrigid grainup wood paving blocks providing; arcs. of age rings in cross sections parallel to the pavement face of the block, said blocks beinn independently removable from the face.

of the pavement, and said blocks havin' within the contour of the blocks, intercep lion means for the longer are age rings, said. interception means extending through the pavement from the pavement face to break up longer are: age rings into a. plurality lot a re sections whereby expansion and contraction disturbances may be dissipa-tedwithin the region as laid of the-respective blocks of the pavement.

Q. in a pavement comprising oblong graiirup wood blocks disposed in rows, the joints of the blocks of one row of the lon Way of the blocks being; staggered with the joints of ihe Mocks of the adjuc c TON. of Hm 11050 the means 0'? taking care of 010: can fion embodying Having Said bloL-ks infill uuiiy rigid wiiih the short-31' ('1 age, o zux'hing from J us then: m; 

